(1) Field of the Invention
The present invention relates to a driving device for a flexible lance.
(2) Description of Related Art
A flexible lance is used to clean the ducts in a heat exchanger. In the course of time these ducts become fouled such that the through-flow is blocked to a greater or lesser degree. In order to enable the heat exchanger to function optimally again the ducts, particularly the pipes thereof, are cleaned by injecting liquid under high pressure through these ducts using a high-pressure lance.
A known device makes use of lances in the form of high-pressure hoses which carry a high-pressure injection nozzle on their front end. These hoses are pushed from a reel into the heat exchanger pipes. After the high-pressure source for the washing liquid has been set into operation, the dirt is removed from the duct and the hose can herein be pushed further into the pipe, until the whole length of the pipe is cleaned.
In the known device the flexible lance is taken up on a reel which is rotatable. A co-displacing enclosure is formed around the reel so that the hose can be unwound from the reel with drive power in order to push the hose into the duct for cleaning. It is noted that the high-pressure nozzle of the lance is herein embodied such that a part of the high-pressure liquid is sprayed out backwards, so that a pulling force is developed.
The known device is herein disposed fixedly in front of the heat exchanger to be cleaned.
The object of the invention is to provide a device of the present type, which can be readily manipulated and wherein particularly heat exchangers which are difficult to access and placed vertically can be properly cleaned.
This object is achieved with the device according to the invention, the embodiment of which is shown in the annexed figures.